Description
Overview
The Flowmaster Flow FX Axle-Back Exhaust System is engineered to give your late-model Mustang a deeper, more purposeful voice without the complexity of a full exhaust replacement. Designed specifically for 2005-2010 Ford Mustang GT, Shelby GT, GT500 (including GT500KR), California Special and Bullitt models equipped with the 4.6L and 5.4L engines, this axle-back kit swaps out the restrictive factory hardware for genuine Flowmaster performance components engineered to bolt directly into place.
At the heart of the system is a pair of compact, round Flow FX “straight-through” performance mufflers. These large 3.00-inch core mufflers are built to flow, delivering maximum performance while producing the deep, aggressive-to-moderate tone Flowmaster is known for. Constructed from bright 409S stainless steel, they’re made to stand up to heat and the elements mile after mile.
Key Benefits
Every detail of the Flow FX axle-back is aimed at real-world usability. The dual 3.00-inch mandrel-bent stainless steel tubing promotes smooth, unrestricted exhaust flow, while the system reuses the factory hanger locations for a straightforward, no-drama installation. Because it’s an axle-back design, you upgrade sound and appearance without touching the mid-pipe or upstream components.
- Dual 3.00-inch mandrel-bent stainless steel tubing for smooth exhaust flow
- Round Flow FX “straight-through” performance mufflers with large 3.00-inch cores
- Bright 409S stainless steel muffler construction
- Large 4.50-inch ceramic-coated stainless steel tips with embossed logo that fill the factory lower-valance cutouts
- Bolts to factory hanger locations for easy installation
- CARB (California) compliant with a Prop 65 warning
- Includes all necessary parts, hardware, and detailed instructions
- Covered by Flowmaster’s Lifetime Limited Warranty
Sound & Style
The Flow FX mufflers are tuned to deliver a deep tone with an aggressive yet moderate character — assertive enough to announce your Mustang’s presence, refined enough to live with every day. Dual tail pipes are capped with large 4.50-inch ceramic-coated stainless steel tips featuring an embossed logo, filling out the factory exhaust cutouts in the lower valance for an OEM-plus finished look. The muffler measures 32.50 inches overall with a 3.00-inch outlet diameter.
Fitment
This system is designed for 2005-2010 Ford Mustang GT, Shelby GT, GT500, California Special and Bullitt models with the 4.6L and 5.4L engines. GT500KR models are included in the fitment. As a CARB-compliant, 50-state legal design, it’s a smart choice for enthusiasts who want more sound and flow while staying emissions conscious.
Backed by Flowmaster’s Lifetime Limited Warranty and shipping complete with mufflers, hardware, and installation instructions, the Flow FX Axle-Back is a proven, direct-fit upgrade for owners who want a serious step up in tone and presence with a bolt-on install.
